Continuous casting of non-ferrous metals

ABSTRACT

A continuous casting machine is disclosed of the kind having a mold formed by a cooperating pair of endless sets of articulated mold blocks which are driven at the same speed so that over an advancing portion of their run they engage with each other and define between them a moving mold cavitiy. The advancing portion of the run of the blocks is straight and inclined to the horizontal at 45* or less. The blocks of the lower set move downwards as they leave the advancing portion of the run, and to prevent their weight from pulling apart the blocks occupying the advancing portion of the run, a brake is provided at the downstream end of the advancing portion of the run. The action of the brake opposes the pull exerted by the weight of the blocks leaving the advancing portion.

United States atent [191 Gyongyos 1 Sept. 17, 1974 CONTINUOUS CASTING OFNON-FERROUS METALS [75] Inventor: Ivan Gyongyos, Montana,

21 Appl. No: 447,151

Related US. Application Data [63] Continuation of Ser. No. 309,800 Nov.27. 1972,

3.11 1,824 11/1963 Firth 64/30 C 3,342,251 9/1967 Nagin 3,605,868 9/1971Giadorou 164/279 Primary Examiner-J. Spencer Overholser AssistantExaminer-John S. Brown Attorney, Agent, or FirmErnest F. Marmorek [57]ABSTRACT A continuous casting machine is disclosed of the kind having amold formed by a cooperating pair of endless sets of articulated moldblocks which are driven at the same speed so that over an advancingportion of their run they engage with each other and define between thema moving mold cavitiy. The advancing portion of the run of the blocks isstraight and inclined to the horizontal at 45 or less. The blocks of thelower set move downwards as they leave the advancing portion of the run,and to prevent their weight from pulling apart the blocks occupying theadvancing portion of the run, a brake is provided at the downstream endof the advancing portion of the run. The action of the brake opposes thepull exerted by the weight of the blocks leaving the advancing portion.

4 Claims, 6 Drawing Figures CONTINUOUS CASTING OF NON-FERROUS METALSThis is a continuation, of application Ser. No. 309,800, filed Nov. 27,1972, and now abandoned.

A machine for the continuous casting of strips of non-ferrous metals,such as aluminum and aluminum alloys, and hereinafter referred to as ofthe kind described, has a mold formed by a cooperating pair of endlesssets of articulated mold blocks which are driven at the same speed sothat over an advancing portion of their run they engage with each otherand define between them a moving mold cavity.

In machines of this kind, the two endless sets of mold blocks arepreferably driven by gearwheels which engage with toothed edge segments,each mold block having two of these segments, one at each side of themachine. The driving gearwheels, also one at each side of the machine,can engage with the toothed edge segments at any straight portion of therun of the blocks. The advancing portion of the run is generallystraight as is a return portion.

An example of such a machine is disclosed in U.S. Pat. No. 3,570,586 ofLauener. In this machine the sets of mold blocks are connected toguiding and driving parts by supporting and attachment devices which arethermally insulating. The abovementioned patent also discloses thecasting of wide strips, for example, in column 7, lines 51 and 52.

In the operation of machines of the kind described it is important toensure that over the advancing portion of their run, the individual moldblocks of each set do not become separated from each other, leaving gapsbetween them. In a machine in which the advancing portion of the run isinclined for instance at a downward angle between and 45 to thehorizontal, gaps can open up between the individual mold blocks of thelower set because of the pull applied by the weight of the blocks whichmove downwards away from the advancing portion of their run beforereturning to the upstream end of the machine. These gaps are additionalto the unavoidable gaps resulting from manufacturing tolerances. Anundesired looseness can also be produced in the upper set of blocks.

In accordance with the present invention in a machine of the kinddescribed with the advancing portion of the run of the blocks inclinedat an angle between 0 and 45 to the horizontal, at least the lower oneof the two sets of blocks is provided with a brake at the downstream endof the advancing portion. The action of the brake opposes the pull dueto the weight of the blocks moving downwards away from the advancingportion and thus prevents the weight from opening up gaps between blockswhile moving along the advancing portion of the run, or at least reducessuch gaps.

The brake is preferably adjustable so that the braking force applied tothe mold blocks can be regulated to suit operating conditions. It isusually desirable for brakes to be provided on both sides of the machineand to be set tightly enough to prevent entirely any opening up of gapsbetween the mold blocks. However a slight gap is not a serious matter,provided that it is too narrow to allow molten metal to enter. An entireabsence of gaps is necessary only if the cast strip has to be of thehighest quality.

One example of a machine of the kind described, and two examples ofbrakes with which the machine may,

in accordance with the invention, be provided are illustrated in theaccompanying drawings, in which:

FIG. 1 is a diagrammatic perspective view of the machine;

FIG. 2 is a perspective view of the lower set of mold blocks seen in thedirection indicated by the arrow 11 in FIG. 1;

FIG. 3 corresponds to FIG. 2, but shows the lower set of blocks fittedwith the first example of a brake;

FIG. 3a illustrates the side of the machine opposite to the one shown inFIG. 3;

FIG. 4 corresponds to FIG. 3, but shows a brake of differentconstruction; and,

FIG. 5 shows a detail, drawn to a larger scale, of the brake representedin FIG. 4.

FIG. 1 shows a machine of the kind described, with an upper set 10 ofmold blocks 12 and a lower set 11 of blocks 13. The curved arrowsindicate the direction of circulation of the two sets of blocks. Over anadvancing portion 14 of their run, each block is in contact both withadjacent blocks of itsown set and with an opposing block of the otherset. The advancing portion 14 of the run is rectilinear and inclined atan angle of 3 to the horizontal. In the present example, six blocks ofeach set occupy the advancing portion of the run at any moment.

The upper mould blocks 12 have flat faces, whereas each lower mold block13 has a recess 15, which forms the interior of the mold, the upper moldblocks acting merely as flat covers for the mold. The depth of therecesses 15 determines the thickness of the emerging cast strip 16.

The mold blocks of each set are interconnected by thermally insulatingsupporting and attachment parts to guiding parts, which are not shown inthe drawing because they are contained within a housing 17. However thedrawing shows toothed edge segments 18 of each block and side drivegearwheels 19, 20, which drive the mold blocks forward over the portion14 of their run. A driving motor is shown at 21.

As shown in FIG. 2, when the machine is in operation gaps 22 open upbetween the individual mold blocks 13 of the lower set 11 over theadvancing portion of their run. These undesired gaps open up due to thepull of the mold blocks at the downstream part of the lower set 11,where the mold blocks move downwards. The effect obtained is that thefloor of the mold has gaps between the lower mold blocks 13 over theadvancing portion 14 of the run, as represented in FIG. 1, that is tosay where the lower mold blocks 13 are in contact with the upper moldblocks 12. These gaps in the floor of the mold are obviouslyundesirable.

To overcome this problem, a braking effect is applied at least to thelower mold blocks 13 at the downstream end of the advancing portion ofthe run, so as to close the gaps, or rather so as to prevent the gapsfrom opening up in the first place. FIG. 3 shows a braking device gapsfrom opening up between them over the length 14.

There are driving gear trains 19, 20 and brakes 23, 24, 25 and 26 onboth sides of the machine, the axles carrying the gearwheels 19, 20 and24 extending right across the machine, between the two sides. Bothdriving and braking are therefore equally applied at both sides of themachine. While FIG. 3 illustrates the right side of the lower mold blockchain when view in the direction of casting, FIG. 3a illustrates theleft side of the same block chain when viewed in the direction ofcasting.

FIGS. 4 and show a braking arrangement of different construction. Atoothed wheel 27 engages with the toothed edge segments 18 of the lowermold blocks 13. A braking effect is applied adjustably to the wheel 27as follows. The gearwheel 27 has a central drilling countersunk at bothends to give conical internal surfaces 28 which engage with the surfacesof two conical rings 29. When the machine is in operation frictionbetween the surfaces 30 of the conical rings 29 and the internal conicalsurfaces 28 of the gearwheel 27 produces a braking effect which, throughthe gearwheel 27 and through the toothed edge segments 18, is applied tothe lower mold blocks 13, preventing gaps from opening up between them.The conical rings 29 are spline mounted on a shaft 31, so that theycannot rotate on the shaft. At its base the shaft 31 is welded, at 32,to the wall of the housing 17. The shaft 31 stops here, that is to sayit does not extend across the machine to the braking device on the otherside. The two conical rings 29 are thrust towards each other by platesprings 33, which are compressed by means of a nut 34. By adjusting thenut 34 the operator of the machine can sensitively adjust the thrustswith which the two conical rings 29 are thrust towards each other, andtherefore the friction between the conical rings 29 and the gearwheel27, giving a sensitive adjustment of the braking effect applied to thelower set 11 of mold blocks.

A variety of other braking arrangements can if desired be used, forexample a brake shoe can be arranged to act directly on the outer edgesof the toothed edge segments 18.

I claim:

l. A machine for the continuous casting of non- 4 ferrous metal stripcomprising articulated upper and lower endless sets of molded blockswherein each said set of mold blocks is operable for movement around aclosed run, mounting means for each said set of mold blocks forsupporting said set of mold blocks with a succession of said blocks ofeach said set being disposed rectilinearly to form an advancing portionof said runs that is inclined to the horizontal at an angle between 0and 45, said lower set of said mold blocks moving downwardly uponleaving the advancing portion of said runs, the succession of saidblocks of said upper set being in engagement with the correspondingsuccession of said lower set of mold blocks for forming a mold cavitytherebetween, driving means arranged on both sides of said machine fordriving said endless sets of mold blocks around said respective closedruns in synchronism with one another and continuously operatingfrictional braking means disposed to engage a portion of said moldblocks of at least said lower set proximate the downstream end of saidadvancing portion, said frictional braking means exerting a continousrestraining force to said lower set of mold blocks in a directionopposite to the movement of said lower set of mold blocks for preventingthe weight of said lower set of mold blocks at the downstream end ofsaid advancing portion for pulling apart said mold blocks in theremaining upstream section of said advancing portion said continuouslyoperating frictional braking means being positioned on both sides ofsaid advancing portion proximate the downstream end thereof.

2. A machine according to claim 1, including a plurality of toothedsegments, at least one of said segments being carried by each of saidmold blocks, and said frictional braking means being adapted to engagesaid tooth segments.

3. The machine as claimed in claim 1, wherein said continuouslyoperating frictional braking means is adjustable.

4. The machine as claimed in claim 1, wherein said braking meanscomprises a brake shoe on each side of said machine.

1. A machine for the continuous casting of non-ferrous metal stripcomprising articulated upper and lower endless sets of molded blockswherein each said set of mold blocks is operable for movement around aclosed run, mounting means for each said set of mold blocks forsupporting said set of mold blocks with a succession of said blocks ofeach said set being disposed rectilinearly to form an advancing portionof said runs that is inclined to the horizontal at an angle between 0*and 45*, said lower set of said mold blocks moving downwardly uponleaving the advancing portion of said runs, the succession of saidblocks of said upper set being in engagement with the correspondingsuccession of said lower set of mold blocks for forming a mold cavitytherebetween, driving means arranged on both sides of said machine fordriving said endless sets of mold blocks around said respective closedruns in synchronism with one another and continuously operatingfrictional braking means disposed to engage a portion of said moldblocks of at least said lower set proximate the downstream end of saidadvancing portion, said frictional braking means exerting a continousrestraining force to said lower set of mold blocks in a directionopposite to the movement of said lower set of mold blocks for preventingthe weight of said lower set of mold blocks at the downstream end ofsaid advancing portion for pulling apart said mold blocks in theremaining upstream section of said advancing portion said continuouslyoperating frictional braking means being positioned on both sides ofsaid advancing portion proxImate the downstream end thereof.
 2. Amachine according to claim 1, including a plurality of toothed segments,at least one of said segments being carried by each of said mold blocks,and said frictional braking means being adapted to engage said toothsegments.
 3. The machine as claimed in claim 1, wherein saidcontinuously operating frictional braking means is adjustable.
 4. Themachine as claimed in claim 1, wherein said braking means comprises abrake shoe on each side of said machine.